Because of the uncertainties concerning successful application of renewable-energy sources, and the impact of energy efficiency, both fossil and nuclear energy conversion will still be needed for a long time. Especially because it is GHG-free, nuclear power should be kept alive as an electricity-generation option. A major concern is the conservation of the western nuclear know how: Because of the liberalization of the market for electricity, short-term thinking reigns, and no new nuclear plants are expected to be ordered during the next decade. Existing nuclear plants should be kept in operation as long as it is justified from a safety and economic viewpoint. When they have reached their real end-of-life - i.e., when it becomes too expensive to intervene technically to keep the plant sufficiently safe - they can be shut down, and should be replaced by new nuclear plants. (orig.)